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Measurement of the 3He Spin-Structure Functions and of Neutron (3He) Spin-Dependent Sum Rules at 0.035<Q^2<0.24 GeV^2

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 نشر من قبل Alexandre Deur
 تاريخ النشر 2019
  مجال البحث
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The spin-structure functions $g_1$ and $g_2$, and the spin-dependent partial cross-section $sigma_mathrm{TT}$ have been extracted from the polarized cross-sections differences, $Delta sigma_{parallel}hspace{-0.06cm}left( u,Q^{2}right)$ and $Delta sigma_{perp}hspace{-0.06cm}left( u,Q^{2}right)$ measured for the $vec{^textrm{3}textrm{He}}(vec{textrm{e}},textrm{e})textrm{X}$ reaction, in the E97-110 experiment at Jefferson Lab. Polarized electrons with energies from 1.147 to 4.404 GeV were scattered at angles of 6$^{circ}$ and 9$^{circ}$ from a longitudinally or transversely polarized $^{3}$He target. The data cover the kinematic regions of the quasi-elastic, resonance production and beyond. From the extracted spin-structure functions, the first moments $overline{Gamma_1}hspace{-0.06cm}left(Q^{2}right)$, $Gamma_2hspace{-0.06cm}left(Q^{2}right)$ and $I_{mathrm{TT}}hspace{-0.06cm}left(Q^{2}right)$ are evaluated with high precision for the neutron in the $Q^2$ range from 0.035 to 0.24~GeV$^{2}$. The comparison of the data and the chiral effective field theory predictions reveals the importance of proper treatment of the $Delta$ degree of freedom for spin observables.



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